Name: ________________________________ Section: ________Date: __________________
Lab – Moles and Coefficients
PROBLEM UNDER INVESTIGATION:
In this lab, solid iron is added to a solution of copper(II) sulfate, producing solid copper and a solution of
either iron(II) sulfate or iron(III) sulfate. We will experimentally determine which.
PRE-LAB:
Solid iron is added to a solution of copper(II) sulfate, producing solid copper and a solution of iron(?)
sulfate.
1. What is the formula for copper(II) sulfate?
2. What is the formula for iron(II) sulfate?
3. What is the formula for iron(III) sulfate?
4. Write two balanced chemical equations for this reaction, one using iron(II) sulfate and one using
iron(III) sulfate.
PROCEDURE:
Preparing the copper(II) sulfate solution:
 Mass a clean dry 100 ml.beaker.
 Measure 0.06 moles CuSO4 crystals and add to beaker. How many grams is that?
 Measure 50.0 ml.H2O and add to beaker.
 Heat gently to just below boiling.
 DO NOT ALLOW IT TO BOIL!!!
 Heat until crystals dissolve.
How many grams are there in 0.06 moles of CuSO4? (Show your calculation!)
Preparing the solid iron:
 While one partner is dissolving the crystals, another partner should measure out 0.04 moles of
iron filings.
How many grams are there in 0.04 moles of iron filings? (Show your calculation!)
Observing the reaction:
 Add the iron filings small amounts at a time to the copper sulfate solution, stirring constantly.
 Then let it sit for 10 minutes while the reaction proceeds.
 Record your observations here:
Isolating the copper:
 Decant the liquid into a 250 ml beaker.
 Do not disturb the solid at the bottom of the 100 ml beaker.
 Add about 10 ml. water, stir to wash off the solid. Let it settle and then decant. Repeat.
 Spread the solid out on the bottom of the beaker and leave to dry.
When you wash the solid with 10 ml. of water, what are you removing? Why is that important?
Measuring the mass of the copper:
 The next day (or the next class period) mass the beaker and the dry copper metal.
What is the mass of solid copper?
How many moles is this? (Show your calculation!)
What is the ratio of moles of solid iron used to moles of solid copper produced?
Where did the iron filings go?
What is the correct formula for the iron sulfate produced in this reaction?